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As public opposition to license plate recognition grows, so do the claimed workarounds. The latest to go viral is a reflective spray coating, available at hardware stores for ~$30, that social media posts across Reddit, TikTok, Instagram, and other platforms claim will stop LPR cameras from reading a plate altogether, not just wash it out under a flash.
IPVM bought it, applied it at multiple coat thicknesses across multiple state plates, and tested it against five LPR systems.
IPVM purchased Rust-Oleum 214944 and tested it across:
- Five LPR systems (Rekor, Genetec, Axis, Hanwha, Verkada)
- Both daytime and night/IR conditions
- Multiple state plates
- Thin, thick, and multiple coat thicknesses
See also IPVM's prior reflective spray testing:
- License Plate Recognition Blocker "Shield License" Tested
- PRC-China Company Selling License Plate Blocking Spray Analyzed
- Reflective Stickers For Blocking License Plate Recognition Tested
Executive Summary
Rust-Oleum 214944 did not block or degrade license plate recognition in any tested condition. Testing across five LPR systems (Rekor, Genetec, Axis, Hanwha, and Verkada) showed no change in plate reads in daylight, at night under IR, or under a handheld camera flash. Thin coats, thick coats, and multiple coats all produced identical results. Nighttime photos taken with a handheld camera flash showed no washout; if anything, the coated plate was more legible than the uncoated baseline. This is the third distinct reflective spray product IPVM has tested, and all three failed to affect LPR performance.
The spray's viral appeal stems from a misunderstanding of how LPR systems work. Social media demonstrations use a phone flashlight held at close range and plate level, producing visible overexposure on a phone camera, an effect people assume will carry over to LPR cameras. But LPR cameras don't use a flash; they read plates using continuous or pulsing IR illuminators, and any reflection off a coated plate would have to come from that IR light bouncing back to the camera's sensor. In our testing, that IR reflection did not occur under any condition. The mismatch is easy to miss and easy to exploit, whether by posters who don't understand LPR or by vendors who don't understand it themselves.
What Rust-Oleum 214944 Is
Rust-Oleum 214944 is a legitimate specialty product designed for safety markings, road signage, and crafts, not for use as a camera countermeasure. Its reflective finish comes from glass microspheres suspended in a clear carrier, which reflect light back toward its source. Social media accounts have repurposed this property, claiming the spray overexposes a license plate when hit by a traffic or LPR camera flash, washing out the characters.
Rust-Oleum makes no such claim. The camera-blocking application originates entirely from social media, where videos demonstrate the effect using a phone flashlight held close and at plate level, conditions that do not reflect how LPR or enforcement cameras operate.
214944 is Rust-Oleum's only reflective spray SKU. Other nearby product numbers belong to unrelated lines, such as marking paints and striping equipment, so there is no ambiguous or closely related variant. 214944 is the specific and only product anyone has claimed can block LPR.
Test Setup
Testing was conducted at the IPVM test facility in Pennsylvania. Five LPR systems were tested:
- Rekor Edge Pro
- Genetec Autovu Cloudrunner
- Axis License Plate Verifier
- Hanwha Road AI
- Verkada LPR
Multiple state license plates were used. Each plate was tested uncoated as a baseline, then tested with a thin single coat, a thick single coat, and multiple coats, with each coat allowed to fully dry before testing. Conditions tested included full daylight, direct sunlight, night under continuous IR, night under pulsing IR (Genetec Autovu), and night using a handheld camera flash to replicate the close-range effect shown in viral videos.
Daytime Results
No LPR system showed any change in plate reads under daylight conditions after the spray was applied. Rekor read all coated plates at the same accuracy as the uncoated baseline. Under direct sunlight, where the retroreflective properties of the spray would theoretically be most active, reflectivity remained unchanged and all five systems captured full plate reads.
Night and IR Results
Under continuous IR, pulsing IR, and a handheld camera flash, all five systems read coated plates without degradation. The Genetec Autovu Cloudrunner, which pulses IR as vehicles pass, showed no difference between coated and uncoated plates. Nighttime photos taken with a handheld camera flash produced the clearest illustration of the spray's ineffectiveness: the coated plate showed no washout, and, if anything, the flash made the plate characters more legible than the uncoated baseline.
The Genetec capture below shows a full-vehicle top image, which is typical of how Autovu sometimes displays plate captures and does not indicate a problem. The plate itself was fully visible and showed no IR reflection effect.
Coat Thickness Made No Difference
A thin single coat, a heavy single coat, and multiple stacked coats all produced the same result: no change in plate readability. LPR systems read every coated plate at full accuracy regardless of how much product was applied.
Why the Spray Does Not Work Against LPR
The social media demonstrations of Rust-Oleum 214944 are produced under conditions that do not replicate how LPR cameras operate. Retroreflective materials send light back toward its source most strongly when the light source and the receiver are nearly co-located and at close range. In the viral videos, a flashlight is held at plate level, point-blank, creating the overexposure effect on a phone camera.
LPR cameras are typically mounted above and to the side of the lane, not at plate level, and they do not use a visible flash. The IR emitters in dedicated LPR cameras use wavelengths and intensities calibrated to illuminate plates under those mounting geometries. The glass microspheres in Rust-Oleum 214944 do not produce meaningful retroreflection at the oblique angles and distances typical of LPR deployments, and the cameras' auto-exposure adjusts for ambient IR return regardless. Pulsing IR systems like the Genetec Autovu are specifically designed to compensate for variable plate reflectivity.
Versions Used
- Rekor Edge Pro: 4.2.4
- Genetec Autovu Cloudrunner: No Firmware Given
- Axis License Plate Verifier: 3.0.8
- Hanwha Road AI: 2.23.03_20250827_R90, Road AI 7.3605
- Verkada LPR: No Firmware Given